<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>盒子模型-组成</title>
  <style>
    div {
      width: 200px;
      height: 200px;
      background-color: pink;

      /* 内容与盒子边缘之间 */
      padding: 20px;
      border: 1px solid #000;
      /* 出现在盒子外面，拉开两个盒子之间的距离 */
      margin: 50px;
    }
  </style>
</head>
<body>
  <div>div 标签</div>
</body>
</html>